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<a name="Creating-and-freeing-a-hash-table"></a>
<h4 class="subsection">2.18.1 Creating and freeing a hash table</h4>
<a name="index-bfd_005fhash_005ftable_005finit"></a>
<a name="index-bfd_005fhash_005ftable_005finit_005fn"></a>
<p>To create a hash table, create an instance of a <code>struct
bfd_hash_table</code> (defined in <code>bfd.h</code>) and call
<code>bfd_hash_table_init</code> (if you know approximately how many
entries you will need, the function <code>bfd_hash_table_init_n</code>,
which takes a <var>size</var> argument, may be used).
<code>bfd_hash_table_init</code> returns <code>FALSE</code> if some sort of
error occurs.
</p>
<a name="index-bfd_005fhash_005fnewfunc"></a>
<p>The function <code>bfd_hash_table_init</code> take as an argument a
function to use to create new entries.  For a basic hash
table, use the function <code>bfd_hash_newfunc</code>.  See <a href="Deriving-a-New-Hash-Table-Type.html#Deriving-a-New-Hash-Table-Type">Deriving a New Hash Table Type</a>, for why you would want to use a
different value for this argument.
</p>
<a name="index-bfd_005fhash_005fallocate"></a>
<p><code>bfd_hash_table_init</code> will create an objalloc which will be
used to allocate new entries.  You may allocate memory on this
objalloc using <code>bfd_hash_allocate</code>.
</p>
<a name="index-bfd_005fhash_005ftable_005ffree"></a>
<p>Use <code>bfd_hash_table_free</code> to free up all the memory that has
been allocated for a hash table.  This will not free up the
<code>struct bfd_hash_table</code> itself, which you must provide.
</p>
<a name="index-bfd_005fhash_005fset_005fdefault_005fsize"></a>
<p>Use <code>bfd_hash_set_default_size</code> to set the default size of
hash table to use.
</p>



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